1. Field of the Invention
This invention relates to a method and apparatus for optical recording, and more particularly, to a method and apparatus for recording data on a Blu-ray disk.
2. Description of the Related Art
Conventional optical disks, such as digital versatile disks (DVD) or video compact disks (VCD), are extensively used in business activities or family life. They are usually used to store a mass of video, audio or other digital data, such as movies, music files, application software, etc. In order to make the optical disks capable of having a larger storage capacity, a standard for Blu-ray disks has been defined recently to satisfy the future requirements of users, in which a Blu-ray disk has a storage capacity more than five times greater than that of a DVD.
Reference is made to FIG. 4, which is a flowchart diagram that illustrates the encoding process for a Blu-ray disk. Firstly, a means of encoding a Blu-ray disk divides the user data into frames, each of which has 2048 data bytes and 4 bytes of error detection codes (EDC). 32 frames of the user data is taken to form a data frame 200. The data frame 200 is re-arranged to form a data block 202, which is a data matrix with 304 columns and 216 rows. Before being re-arranged, every frame of the user data is scrambled to form a scrambled data frame. Thereafter, the encoding means generates 32 parity rows of long distance error correction codes (LDC) for every data block 202 to form a LDC block 204. Every column of the LDC block 204 is a LDC code. Hence, one LDC block 204 has 304 LDC codes. Subsequently, the LDC block 204 is re-arranged to form a LDC cluster 206, which is a data matrix with 152 columns and 496 rows. In the re-arranging process, the LDC block 204 is interleaved twice to reduce burst errors.
On the other hand, to facilitate data accessing, the logical address and control data 208 and physical address 210 are added in the encoding process, and the data and addresses are also encoded. For every user frame 200, the encoding means will provide the logical address and control data 208 of 32×18 bytes and the physical address 210 of 16×9 bytes. In the encoding process, the logical address and control data 208 and the physical address 210 are combined and re-arranged to form an access block 212, which is a data matrix with 24 columns and 30 rows. Thereafter, the encoding means generates 32 parity rows of the burst indicator subcodes (BIS) for the access block 212 to form a BIS block 214. Every BIS block 214 is re-arranged to form a BIS cluster 216, which is a data matrix with 3 columns and 496 rows. In the re-arranging process, the BIS block 214 is interleaved once.
After the LDC cluster 206 and the BIS cluster 216 are formed, the encoding means divides the LDC cluster 206 into four equal parts and divides the BIS cluster 216 into three equal parts. Thereafter, the encoding means inserts the parts of the BIS cluster 216 into the LDC cluster 206 and provides a frame sync to form a physical cluster 218. Lastly, the encoding means modulates the data of the physical cluster 218 and proceeds with the recoding procedure to form an error correction modulation block on the optical disk. The above data sequence and encoding are required by the Blu-ray standard.